This invention relates to electrically insulating thin film processes that are hermetic and that are used to encapsulate integrated circuits (ICs) for the purpose of forming a protective package for an electronic circuit, where the ICs are applicable to devices that are implanted in living tissue, such as neural prostheses or retinal electrode arrays. The package may have electrical feedthroughs to connect electrically to the outside environment. The electric circuit may interface with the outside environment optically (for example, infra-red or laser) or via electromagnetic means, such as radio frequency (RF) and thus it may not need an exposed feedthrough. Additionally, the hermetic film may be it may not need an exposed feedthrough. Additionally, the hermetic film may be made selectively electrically conductive in certain regions to facilitate signal transmission or power transmission.
The main drawback to thin film packaging of electronic circuits that are implanted in living tissue is that the process is typically three-dimensional since the entire IC needs to be packaged (encapsulated in a thin film). This results in long deposition times that add cost and that could exceed the thermal budget of the electronic circuits, thereby destroying the device. The invention describes a device and means for reducing the required deposition process time by allowing an equivalent package to be constructed in a two-dimensional deposition that covers several chips at the same time at the wafer level.